The Expanding Grip of the Expansion Screw

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We are based in Shandong, China, start from 2014,sell to North America(20.00%),South America(20.00%),Eastern Asia(20.00%),Western Europe(20.00%),South Asia(20.00%). There are total about 5-10 people in our office.
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Fasteners,guide,bearing.
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Of all the fastener types engineered over the decades, perhaps none is more ingenious than the expansion screw. Designed specially for gripping into brittle materials like concrete, brick and plaster, this unique screw owes its holding power to an elegant yet simple mechanism.

The key lies in its two-piece shank design. The expansion screw utilizes an outer smooth shank and inner cone-shaped wedge. As the screw is driven into a pre-drilled hole, the wedge pushes outward against the base material, exerting tremendous lateral pressure to create a tight, wedging effect. This distributes force over a wide area rather than concentrating stress in one spot, preventing cracks and blowouts in fragile substrates.

The outer sleeves come in various materials like hardened steel, stainless steel or thermoplastic to suit different applications. The screws are commonly used in construction for hanging fixtures on concrete walls or anchoring wood framework. The non-corrosive nature of certain expansion screw types makes them ideal for exterior applications. The ribbed underhead grips surfaces firmly.

Available in sizes from M5 to M12, expansion screws offer reliable anchor points from light duty shelving to heavy equipment weighing hundreds of pounds. They can be paired with various head styles, drive types and thread lengths for desired aesthetics and utility. Tightening against a fixture compresses the wedge even further for an incredibly rigid, vibration-resistant hold.

With its deceptively simple wedge-based operation, the ingenious expansion screw has become an indispensable fastener for creating robust anchor points in stone, concrete and other friable substrates. The grip it generates is a testament to clever engineering transcending brute strength through pure mechanical logic.